- Up to the temperature of 350°F, preheat the oven. Take a large casserole dish, butter it and then set it aside.
- In a large skillet, heat olive oil over medium heat. With pepper, Italian seasoning and slat, season the chicken from both the sides. To the pan, add this and cook for about 4-5 minutes till the chicken is cooked through. Wipe the skillet clean after removing the chicken from it. Before slicing the chicken crosswise, allow it to rest for about 5 minutes.
- Over medium heat, return the skillet to the skillet. To this, add garlic and butter and sauté for about 30 seconds till, the garlic is fragrant and butter is melted. Into the garlic and butter, whisk the flour and for about 1 minute more till the mixture is golden. Pour the half-an-half gradually with constant stirring. Stir the mixture in Parmesan and bring it to simmer. Allow it to simmer for about 2-3 minutes till the sauce thickens. Season it with pepper and salt to taste.
- Combine chicken, cooked pasta and alfredo sauce in a large bowl. Take the casserole dish and on its bottom, spread half of the pasta mixture. Then with half of the mozzarella, sprinkle it. Top it with more mozzarella after adding more pasta mixture. Bake for about 20 minutes till bubbly. Serve immediately after garnishing with parsley.